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31.
An ocular Thelazia callipaeda infestation was found in a male domestic dog in Taiwan during regular examination. This is the first report of the parasite from pet animal in Taiwan. The infested dog showed normal bodily condition but slight conjunctival congestion. This parasite has been reported in humans in southeast Asia, China and Korea. In 1998, first human case was reported in the central area of Taiwan. The dogs infected with T. callipaeda may have important implication in the infestation of this parasite to humans as reservoir hosts.  相似文献   
32.
This study was conducted to investigate the effects of feeding sows a bulky diet during gestation on their physiological and metabolic adaptations during the peripartum period, and to determine how these effects may relate to sow and piglet performances. From d 26 of gestation until farrowing, gilts were fed diets that contained 2.8 or 11.0% crude fiber (control and high-fiber diets, respectively, n = 9/group). Daily feed allowance provided the same amount of DE daily (33 MJ of DE/d). Throughout lactation, sows were allowed to consume a standard lactating sow diet ad libitum. Litters were standardized to 12 piglets beyond 48 h after birth. On d 105 of gestation, a jugular catheter was surgically implanted. Preprandial blood samples were collected from d 109 of gestation to the day after farrowing and on d 4, 18, and 26 of lactation. Meal tests and glucose tolerance tests were performed on d 109 of gestation and d 4 and 18 of lactation. During gestation, BW and backfat gain did not differ between treatment groups. During lactation, sows fed the high-fiber diet ate an average of 0.94 kg/d more than control sows (P < 0.02). Piglets born from sows fed the high-fiber diet grew faster than piglets from control sows (P = 0.03). Body weight and backfat losses did not differ between the 2 treatment groups. Sows fed the high-fiber diet during gestation had lesser concentrations of leptin before farrowing than control sows (P < 0.01). Leptin concentrations were negatively correlated with feed intake during lactation (P < 0.05). The prepartal increase in prolactin concentrations tended to be greater in sows fed the high-fiber diet than in control sows (P < 0.1). Preprandial concentrations of glucose, NEFA, lactate, and IGF-I fluctuated over time without significant treatment effect. Glucose half-life was shorter in late gestation than during both stages of lactation, but did not differ between sows in the 2 groups. In late gestation, the postprandial increases in glucose and insulin were delayed, and smaller, after a high-fiber meal than after a control meal. During lactation, glucose and insulin profiles after a standard meal did not differ between sows from treatment groups. In conclusion, the greater appetite of lactating sows fed a high-fiber diet during gestation does not seem related to changes in glucose and insulin metabolism and may be partly due to decreased secretion of leptin. The greater feed consumption was accompanied by a faster growth rate of piglets without sparing effect on maternal body reserves.  相似文献   
33.
Setaria digitata and S. marshalli larvae were observed in the cerebrospinal cavity of 2 paralyzed cattle in Taiwan. The 2 affected cattle showed quadriplegia and lumbar paralysis, respectively. At necropsy, which was performed 7 days after the 7-month-old cattle became quadriplegic, three and nineteen S. marshalli larvae as well as two female adult worms were found in the cranial cavity, spinal cavity and peritoneal cavity of the cattle, respectively. Necropsy on the other 8-month-old cattle was also performed 3 days after it showed lumbar paralysis, and ten S. digitata larvae were found in the spinal cavity. In both cattle, many mononuclear inflammatory cells mixed with a few eosinophils were seen accumulated in the connective tissue around the root of the spinal nerves. Infiltration of eosinophils and mononuclear inflammatory cells into the epidura and arachnoidea of the brain were also observed. The major inflammatory cell was lymphocytes, but neutrophils and eosinophils were also present. The number of cells in the cerebrospinal fluid collected initially from the two affected cattle were 105/0.01 ml and 143/ 0.01 ml, respectively. This is the first report of cerebrospinal setariosis in cattle associated with S. marshalli.  相似文献   
34.
Spermatogonial stem cells (SSCs) reside within specialized microenvironments called 'niches', which are essential for their maintenance and self-renewal. In the mammalian testis, the main components of the niche include the Sertoli cell, the growth factors that this nursing cell produces, the basement membrane, and stimuli from the vascular network between the seminiferous tubules. This review focuses on signalling pathways maintaining SSCs self-renewal and differentiation and describes potential mechanisms of regulation of the spermatogonial stem cell niche.  相似文献   
35.
Primordial, pre-vitellogenic and vitellogenic follicles were present in the ovary of the immature ostrich. The oocytes of these follicles were composed of a nucleus surrounded by ooplasm. Central, intermediate and cortical regions formed the ooplasm. The organelles present in these ooplasmic regions varied depending on the stage of follicular development. In primordial and small pre-vitellogenic (100-150 microm in diameter) follicles the central region of the ooplasm was dominated by an accumulation of organelles, which formed Balbiani's vitelline body. In contrast, the central region in vitellogenic follicles was filled with numerous large yolk spheres, many of which contained lining bodies. Numerous lipid droplets interspersed with mitochondria and small yolk spheres formed the intermediate ooplasmic region in primordial and small pre-vitellogenic follicles. In large pre-vitellogenic (150-400 microm in diameter) and vitellogenic follicles the intermediate region contained a greater density of mitochondria and small yolk spheres. Small yolk spheres were observed in the cortical region of pre-vitellogenic follicles. An interesting feature of the cortical region in vitellogenic follicles was the frequent occurrence of Golgi complexes. The results of the study indicate that although the ovarian follicles in the immature ostrich are not ovulated, the components and composition of the ooplasm are similar to those observed in the mature follicles of other avian species.  相似文献   
36.
Lin MY  Lin KJ  Lan YC  Liaw MF  Tung MC 《Avian diseases》2001,45(3):655-658
A strain of Pasteurella anatis (PA) was isolated from the sinus of an adult leghorn laying chicken with sinusitis, nasal discharge, drop in egg production, and low mortality, symptoms initially thought to indicate infectious coryza. The tiny, smooth, whitish colonies were identified as PA. To compare its pathogenicity with that of commercial broilers, nine groups, 10 birds per group, of 10-day-old broilers were individually inoculated with the strain of PA, Pasteurella multocida (PM), or Escherichia coli (EC) by intravenous, intraperitoneal, intramuscular, or subcutaneous inoculation. The PA was determined to cause the signs, lesions, and septicemic death, which are similar to the symptoms of PM or EC infection. At 1 wk postinfection (PI), the mortality rate was between that of PM and EC infection at 1 wk PI. Twenty antimicrobial-containing discs were evaluated, and the isolate was highly sensitive to cetiofer, amoxicillin, lincopectin, and furazolidone. Furthermore, it was moderately sensitive to tetracycline and enrofloxacin and only slightly sensitive to cephalothin, chloramphenicol, flumequine, nalidixic acid, neomycin, oxolinic acid, streptomycin, and trimethoprim. The PA infection was treated successfully with amoxicillin.  相似文献   
37.
Several peripheral blood microfilaria concentration methods that use Acetone (Acetone test), 2% formalin (modified Knott method), 5% Tween 20 solution, distilled water, 1% or 0.1% SDS were compared for their efficacy in detecting Setaria digitata microfilaria in cattle. The Acetone test was found to be more efficacious than the modified Knott method or the 5% Tween 20 solution test for detecting the S. digitata microfilaria in bovine blood. However, besides the Acetone test, the modified Knott method was also found to be suitable for Dirofilaria immitis microfilaria detection in dogs. SDS and distilled water were found not to be effective as hemolytic agent for the disruption of the red blood cell of both the cattle and dogs. Thus, the Acetone test is recommended for the primary screening of microfilaremia of S. digitata in cattle.  相似文献   
38.
Pham TC  Kim HS  Yoon KB 《Science (New York, N.Y.)》2011,334(6062):1533-1538
Applications of zeolite films benefit from alignment of the integrated channels, but methods for film growth have nearly always introduced orientational randomization in the direction normal to the substrate. We now report facile methods to grow silicalite-1 films and pure silica beta zeolite films on substrates with straight or sinusoidal channels positioned uniformly upright at a thickness of up to 8 micrometers. Precise gel compositions and processing temperatures are critical to promote secondary growth on pre-formed oriented crystal monolayers while suppressing self-crystallization in the bulk medium. Preliminary results highlight the potential of these uniformly oriented films in the nonlinear optical response and separation of xylene isomers.  相似文献   
39.
晚疫病是越南马铃薯上最重要的病害。各马铃薯产区均有发生。在江河三角洲地区晚疫病的发生通常比较晚,从12月下旬即第二个生长季后半期开始发病,在1月至2月气温较低、湿度较大时,晚疫病常常严重流行。在Sapa地区(北京高原),整个生长晚疫病对马铃薯作物都是主要威胁。在感病品种上病害的发生和严重度可达到100%。在大叨地区,在干旱季节(11-4月)晚疫病发生最轻,而在雨季(5-10月)严重流行。在越南,还未进行晚疫病菌生物学和流行学方面的基础研究。对晚疫病防治研究主要集中在筛选新的杀菌剂。大部分工作集中在抗病育种和抗病品种的筛选。目前需要进行晚疫综合治疗、流行学、晚疫病菌生物学和抗病育方面的深入研究和培训。  相似文献   
40.
ABSTRACT

After the rice harvest in Japan, rice straw (RS) is usually cut by combine harvester and incorporated into the soil to improve its fertility. In mixed crop–livestock systems, however, RS is collected and used as livestock feed, and cow dung compost (CDC) is then applied to the soil. This system utilizes the residual organic matter from both rice production and livestock husbandry to make each product. CDC application is also considered to improve the fertility of paddy soil. However, the nutrient input from CDC and the effect of CDC application on soil fertility vary among regions and/or soil types. We compared soil fertility between RS application (RS treatment, avg. 32 years) and RS removal plus CDC application (CDC treatment, avg. 21 years) in 79 paddy fields in Mamurogawa town, Yamagata Prefecture, a cold temperate region of Japan, and measured the nutrient contents in the applied RS and CDC. The total C content of RS was significantly higher than that of CDC, whereas the N, P, K, and Si contents of CDC were significantly higher than those of RS. However, there was no significant difference in paddy soil fertility – as measured by soil organic C, total N, CEC, available N, P, and Si, exchangeable K, Ca, and Mg, base saturation percentage, pH, and bulk density – between the treatments. The soil fertility of most fields was adequate by RS or CDC treatment. Thus, leaving RS in paddy fields or removing it and then adding CDC to the paddy fields has a similar effect in maintaining adequate soil fertility for single rice production or rice–livestock production systems.  相似文献   
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